In a multiplicity of environments it is desirable to prevent, eliminate or reduce the existence and/or the intervention of foreign objects. Such types of environment can be airport runways, military bases, home industrial premises etc. A foreign object can be a person, wildlife, birds, inanimate objects, vehicles, fire etc.
For example, in almost every airfield area Foreign Object Debris (FOD) are a major treat to aircraft during take-off from a runway or landing on a runway. FOD such as birds, wildlife or any other object on the runway region or in the air, can be easily sucked into the jet engine of an aircraft, and thereby can cause a more or less severe damage to the jet engine or to the aircraft body. Furthermore, in the worst case a bird or other FOD that has been sucked into a jet engine might cause a crash of the aircraft.
Several attempts to reduce the risk of collision with birds and other wildlife have been made by airport staff, such as frightening the birds with noisy bird scare devices and/or shooting them. However, in order to carry out such attempts, the birds must be spotted in the environment of the runways. Unfortunately, birds are hard to detect by human eyes, they are difficult and sometimes impossible to detect during the day, and are nearly invisible targets for planes at night or during low visibility.
A variety of attempts to control the bird hazard on the airfield have been made. However, such controls provide only a partial solution. An airfield check has to be done several times per hour in order to detect and deter any birds in the airfield areas. The means used for deterring birds include vehicle/human presence, pyrotechnics, and the periodic use of a trained border collie. Furthermore, airport staff is also shifting wildlife by eliminating the existence of nourishment sources such as specific type of plant, puddle, specific bugs etc., which usually attracts the wildlife. However, such nourishment sources in the airport area are relatively hard to detect, and it is required to patrol the airport area with high frequently in order eliminate such sources.
JP 2,001,148,011 discloses a small animal detecting method and a small animal detecting device which can judge an intruder, a small animal, an insect, etc., by an image recognizing means on the basis of image data picked up by a camera. However, this patent refers only to the detection of moving objects that intrude into the monitored area. Furthermore, it does not provide a method to reduce or prevent intrusion from a small animal in the future.
U.S. Pat. No. 3,811,010 discloses an intrusion detection apparatus employing two spaced-apart TV cameras having lines of observation which intersect to form a three dimensional monitored locale of interest and a TV monitor having a display tube and connected to respond to output signals from said TV cameras. The cameras and monitors being synchronized to identify the presence and location of an intruder object in said locale of interest. In another aspect the invention comparator-adder analyzing circuitry is provided between the cameras and monitor such that the monitor is actuated only when the video from both cameras is identical at a given instant. Assuming each camera is directed to observe a different background and that the focus is adjusted to substantially eliminate background signals, then only signals from the intruder object are observed and it is observed only in the monitored locale. However, this patent detects only intrusion objects and it is not directed to static or inanimate objects, and it does not provide the foreseen intruder path, the intruder size, and other useful parameters.
In some cases a radar system is used in order to detect and locate the location of targets or objects in the monitored area. However, it is extremely desirable to perform the detection without exposing the activity of the radar system.
All the methods described above, however, have not yet provided satisfactory solutions to the problem of detecting dangerous objects in the monitored area whether they are static or dynamic, and a way to reduce or eliminate future intrusion of those objects to the monitored area.
It is an object of the present invention to provide a method and apparatus for continuously and automatically detecting the presence of birds, wildlife and of any other FODs that may constitute a menace to the monitored area.
It is another object of this invention to evaluate the degree of danger posed by any detected object.
It is a further object of this invention to monitor the path of the detected dangerous objects and to predict, insofar as possible, their future path.
It is a still further object of this invention to evaluate the probability of collision between of the detected dangerous objects and any aircraft expected to take off from or land in the airfield in which the system of the invention is installed.
It is a still further object of this invention to give the alarm as to any danger revealed from the detection and the monitoring of dangerous objects and from the elaboration of the data acquired from said detection and monitoring.
It is a still further object of this invention to determine, insofar a possible, ways and means for avoiding dangers so revealed and to communicate them to responsible personnel.
It is yet another object of the present invention to provide solution for eliminating future intrusion attempts of wildlife and birds.
It is yet a further object of this invention to provide a method, for continuously and automatically detecting and finding the location of dangerous objects that may constitute a menace to the monitored area, and this without generating a radiation.
It is another object of this invention to provide an enhanced display of the detected dangerous objects.
It is yet another object of this invention to reduce the number of false alarms.
Other objects and advantages of this invention will become apparent as the description proceeds.
While the embodiments of the invention are mainly described with reference to application in airfields, they, of course, also can be used for other applications where there might be a possible problem of intrusion of persons, dangerous objects and/or vehicles into monitored areas, which usually are restricted. It is to be kept in mind that the possibility exists that dangerous objects may also not be natural ones, such as birds, but artificial ones, used for sabotage or terror operations, or a fire endangered the monitored area.
The aircraft taking off or landing on the airfield, and vehicles or persons allowed to be at the monitored area will be designated hereinafter as “authorized bodies”. All other objects, such as birds, wildlife, persons, static objects, artificial objects, fire and any other FODs will generally be called “dangerous objects”.